小尺度管壳式换热器壳侧阻力的特性研究

Research on Shell-side Resistance Characteristics of Small-scale Shell-and-Tube Heat Exchangers

在小型风洞上,以空气为介质,分别对节距比(P/D)为1.5的光滑圆管顺列管束和错列管束进行了流动阻力对比实验,得到了不同来流速度下压降和欧拉数随雷诺数的变化曲线,并对壳侧阻力特性进行了分析,归纳出实验条件下两种结构管束的阻力关联式。结果表明:在相同节距比下,两种结构管束的压降和欧拉数都随雷诺数的增加而增大,但错列管束两端的压降和欧拉数都明显大于顺列管束的。

In a small wind tunnel, with air as the working fluid, the comparative experiment on smooth tube inline and staggered tube bundles was conducted with a same pitch-to-diameter ratio（P/D） of 1.5. At the different flow speeds, the change curves of pressure drop and Euler number variating with Reynolds number were obtained, and the shell-side flow resistance characteristics were analyzed to sum up two structures＇ bundle resistance correlation equations under experimental conditions. The results show that at the same pitch ratio, the pressure drop and Euler number of two structure bundles can rise with the increase of Reynolds number, but the pressure drop and Euler number in staggered tube bundles are significantly greater than that in in-line.